Excessive drinking is an important cause of preventable death and disability in the U.S., with large economic costs. Alcohol disorders are transmitted intergenerationally, and one in four U.S. children is exposed to parent problem drinking, with associated mental and physical health problems that persist into adulthood. Prevention programs have targeted parenting and family environment because of their theoretical roles in early drinking and risk for alcohol disorder. Deviance proneness theories posit that alcoholic parents provide disorganized and conflictual family environments and parenting that lacks support, monitoring, and consistent discipline, which, in turn exacerbate the effects of a genetically-transmitted vulnerability to behavioral under control on alcohol outcomes However, studies are needed to clarify the role of parenting/family environment in the context of correlated genetic risk. Failing to do so risks mis-estimating parenting effects and mis-identifying the optimal content and audiences for intervention. A small literature using candidate genes has tested parenting as a moderator of genetic risk. However, because candidate genes typically explain only small amounts of variance in outcomes, these studies often provide weak, insufficient tests of gene-environment correlation. This R21 introduces a novel approach to this problem by creating two polygenic risk scores to provide a stronger test of gene-environment correlation. Based on theory and research, we create a polygenic risk score to reflect presumed genomic risk for behavioral under control with SNPs from candidate genes in dopaminergic, glutamatergic, GABAergic, and cholinergic muscarinic systems. We use this score to test parenting/family environment as a mediator and a moderator of presumed genomic risk for behavioral under control. We then add an empirically-derived polygenic risk score as an additional measure of gene-environment correlation that explains substantial variance in parenting. This score is composed of SNPs that are significant in association analyses that we conduct with parenting and >1,200 SNPs (relevant to addiction but not specific to behavioral under control and not included in the theory-driven composite). Incorporating this empirically- derived score as an additional gene-environment correlation measure, provides a more rigorous test of parenting and family environment as mediators and moderators of the effects of theory-driven presumed genomic risk for behavioral under control. The project goals will be accomplished through secondary data analysis of a three-generation, longitudinal, genetically informative, study of the intergenerational transmission of risk for alcohol disorders. Analyses will be conducted for two generations of offspring to provide an internal replication. The results will help to clarify the role of parenting and family environment in drinking outcomes, suggest directions for family-based prevention programs, and provide a method for future studies of gene- environment interplay in the development of risk for alcohol disorder.